staging/comedi: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer
to all timer callbacks, switch to using the new timer_setup() and
from_timer() to pass the timer pointer explicitly. Adds pointer back to
comedi device from private struct.

Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: devel@driverdev.osuosl.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/comedi_test.c

@@ -93,6 +93,7 @@ struct waveform_private {
 	unsigned int ai_scan_period;	/* AI scan period in usec */
 	unsigned int ai_convert_period;	/* AI conversion period in usec */
 	struct timer_list ao_timer;	/* timer for AO commands */
+	struct comedi_device *dev;	/* parent comedi device */
 	u64 ao_last_scan_time;		/* time of previous AO scan in usec */
 	unsigned int ao_scan_period;	/* AO scan period in usec */
 	unsigned short ao_loopbacks[N_CHANS];
@@ -201,10 +202,10 @@ static unsigned short fake_waveform(struct comedi_device *dev,
  * It should run in the background; therefore it is scheduled by
  * a timer mechanism.
  */
-static void waveform_ai_timer(unsigned long arg)
+static void waveform_ai_timer(struct timer_list *t)
 {
-	struct comedi_device *dev = (struct comedi_device *)arg;
-	struct waveform_private *devpriv = dev->private;
+	struct waveform_private *devpriv = from_timer(devpriv, t, ai_timer);
+	struct comedi_device *dev = devpriv->dev;
 	struct comedi_subdevice *s = dev->read_subdev;
 	struct comedi_async *async = s->async;
 	struct comedi_cmd *cmd = &async->cmd;
@@ -438,10 +439,10 @@ static int waveform_ai_insn_read(struct comedi_device *dev,
  * This is the background routine to handle AO commands, scheduled by
  * a timer mechanism.
  */
-static void waveform_ao_timer(unsigned long arg)
+static void waveform_ao_timer(struct timer_list *t)
 {
-	struct comedi_device *dev = (struct comedi_device *)arg;
-	struct waveform_private *devpriv = dev->private;
+	struct waveform_private *devpriv = from_timer(devpriv, t, ao_timer);
+	struct comedi_device *dev = devpriv->dev;
 	struct comedi_subdevice *s = dev->write_subdev;
 	struct comedi_async *async = s->async;
 	struct comedi_cmd *cmd = &async->cmd;
@@ -686,8 +687,9 @@ static int waveform_common_attach(struct comedi_device *dev,
 	for (i = 0; i < s->n_chan; i++)
 		devpriv->ao_loopbacks[i] = s->maxdata / 2;
 
-	setup_timer(&devpriv->ai_timer, waveform_ai_timer, (unsigned long)dev);
-	setup_timer(&devpriv->ao_timer, waveform_ao_timer, (unsigned long)dev);
+	devpriv->dev = dev;
+	timer_setup(&devpriv->ai_timer, waveform_ai_timer, 0);
+	timer_setup(&devpriv->ao_timer, waveform_ao_timer, 0);
 
 	dev_info(dev->class_dev,
 		 "%s: %u microvolt, %u microsecond waveform attached\n",

drivers/staging/comedi/drivers/das16.c

@@ -440,6 +440,7 @@ static inline int timer_period(void)
 
 struct das16_private_struct {
 	struct comedi_isadma	*dma;
+	struct comedi_device	*dev;
 	unsigned int		clockbase;
 	unsigned int		ctrl_reg;
 	unsigned int		divisor1;
@@ -525,10 +526,10 @@ static void das16_interrupt(struct comedi_device *dev)
 	comedi_handle_events(dev, s);
 }
 
-static void das16_timer_interrupt(unsigned long arg)
+static void das16_timer_interrupt(struct timer_list *t)
 {
-	struct comedi_device *dev = (struct comedi_device *)arg;
-	struct das16_private_struct *devpriv = dev->private;
+	struct das16_private_struct *devpriv = from_timer(devpriv, t, timer);
+	struct comedi_device *dev = devpriv->dev;
 	unsigned long flags;
 
 	das16_interrupt(dev);
@@ -934,8 +935,7 @@ static void das16_alloc_dma(struct comedi_device *dev, unsigned int dma_chan)
 {
 	struct das16_private_struct *devpriv = dev->private;
 
-	setup_timer(&devpriv->timer, das16_timer_interrupt,
-		    (unsigned long)dev);
+	timer_setup(&devpriv->timer, das16_timer_interrupt, 0);
 
 	/* only DMA channels 3 and 1 are valid */
 	if (!(dma_chan == 1 || dma_chan == 3))
@@ -1044,6 +1044,7 @@ static int das16_attach(struct comedi_device *dev, struct comedi_devconfig *it)
 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
 	if (!devpriv)
 		return -ENOMEM;
+	devpriv->dev = dev;
 
 	if (board->size < 0x400) {
 		ret = comedi_request_region(dev, it->options[0], board->size);

drivers/staging/comedi/drivers/jr3_pci.c

@@ -96,6 +96,7 @@ struct jr3_pci_poll_delay {
 
 struct jr3_pci_dev_private {
 	struct timer_list timer;
+	struct comedi_device *dev;
 };
 
 union jr3_pci_single_range {
@@ -585,10 +586,10 @@ jr3_pci_poll_subdevice(struct comedi_subdevice *s)
 	return result;
 }
 
-static void jr3_pci_poll_dev(unsigned long data)
+static void jr3_pci_poll_dev(struct timer_list *t)
 {
-	struct comedi_device *dev = (struct comedi_device *)data;
-	struct jr3_pci_dev_private *devpriv = dev->private;
+	struct jr3_pci_dev_private *devpriv = from_timer(devpriv, t, timer);
+	struct comedi_device *dev = devpriv->dev;
 	struct jr3_pci_subdev_private *spriv;
 	struct comedi_subdevice *s;
 	unsigned long flags;
@@ -770,7 +771,8 @@ static int jr3_pci_auto_attach(struct comedi_device *dev,
 		spriv->next_time_min = jiffies + msecs_to_jiffies(500);
 	}
 
-	setup_timer(&devpriv->timer, jr3_pci_poll_dev, (unsigned long)dev);
+	devpriv->dev = dev;
+	timer_setup(&devpriv->timer, jr3_pci_poll_dev, 0);
 	devpriv->timer.expires = jiffies + msecs_to_jiffies(1000);
 	add_timer(&devpriv->timer);